Self-concept differentiation is a sign of fragmentation of the self rather than specialization of role identities for its robust relationship with psychological adjustment. However, little is known about the mechanisms underlying the relationship between SCD and psychological adjustment. The aim of this study was to examine the mediating role of self-consistency and congruence in the association between SCD and psychological adjustment, and the moderating role of age in the relationship between SCD and SCC. This moderated mediation model was examined among (...) 158 Chinese retirees, who completed measurements regarding SCD, SCC, psychological well-being, anxiety, and depression. The results showed that SCC partially mediated the links between SCD and the indices of psychological adjustment. Furthermore, age moderated this mediation effect, which was found in mean and high-age participants, but not in low-age ones. Our findings indicate that, at different age stages, the internal mechanisms of SCD affecting psychological adaptation are not the same, and a low differentiated or highly integrated self can serve as an adaptive resource to maintain high subjective well-being of the elderly and protect them from anxiety and depression. (shrink)